[Innovative imaging techniques for urothelial carcinoma]

Imaging guides the staging of urothelial carcinoma and thus plays a central role in treatment decisions. Current guidelines reflect the increasing importance of multiparametric MRI (mpMRI) of the bladder with standardized reporting according to the Vesical Imaging Reporting and Data System (VI-RADS).

This work comprises a narrative, guideline-oriented update based on the European Association of Urology (EAU; 2025 update) and German S3 guidelines (long version 3.0, 2025); recent key studies on VI-RADS-/bpMRT- and PET-based methods; and early targeted imaging approaches.

Multiparametric MRI with classification according to VI-RADS shows high accuracy for discriminating between non-muscle-invasive bladder cancer (NMIBC) and MIBC (area under the receiver operating curve ≈ 0.93-0.95) with good interobserver reliability. Regarding the question "muscle-invasive: yes/no," biparametric MRI (bpMRI) without contrast agent is frequently noninferior to mpMRI in selected settings and reduces the imaging time; however, contrast agent can be useful in the case of unclear findings. For distant and nodal staging, fluorodeoxyglucose positron-emission tomography/CT (FDG-PET/CT) shows an incremental advantage over CT in selected situations. While hybrid PET/MRI implementation is already promising but not yet nationwide, NECTIN-4-targetted PET imaging is still in its infancy and also limited by heterogeneous target expression.

For local staging of urothelial carcinoma, mpMRI-or, in selected cases, bpMRI-should preferably be performed prior to transurethral resection of the bladder tumor (TUR-B) according to VI-RADS standards. Only in selected cases is FDG-PET/CT to be used for N/M staging and restaging. Targeted imaging (e.g., NECTIN-4) and artificial intelligence (AI) are still in the research phase, whereby prospective trials with decision-impact outcomes and standardized implementation and quality processes have priority.